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arXiv · 2111.15138

Emergence of the rho resonance from the HAL QCD potential

Yutaro Akahoshi·Sinya Aoki·Takumi Doi
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Abstract

In this article, we report the $\rho$ resonance study using the HAL QCD method. We calculate the $I=1$ $\pi \pi$ potential at $m_{\pi} \approx 0.41$ GeV by a combination of the one-end trick, sequential propagator and covariant approximation averaging (CAA). Thanks to those techniques, we determine the non-local $I=1$ $\pi \pi$ potential at the next-to-next-to-leading order (N$^2$LO) of the derivative expansion for the first time and obtain the pole of the S-matrix corresponding to the $\rho$ resonance. We also discuss the comparison between our result and a previous calculation, done by L\"uscher's method.

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Yutaro Akahoshi, Sinya Aoki, Takumi Doi. 2021-11-30. Emergence of the rho resonance from the HAL QCD potential. https://arxiv.org/abs/2111.15138

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